Tracker mechanism for musical instruments



Sept. 27, 1932. J. T. AUSTIN v TRACKER MECHANISM FOR MUSICAL INSTRUMENTSFiled May v2O, 1932 I dbhn TA1/lohn Patented Sept. 27, 1932 UNITEDSTATES PATENT OFFICE JOHN AUSTIN, 0F HARTFORD, CONNECTICUT, ASSIGNOR TOTHE AUSTIN ORGAN COMPANY, OF HARTFORD, CONNECTICUT, A CORPORATION OFCONNECTICUT TRACKER MECHANISM FOR MUSICAL INSTRUMENTS Application tiledMay 20,

The present invention relates generally to musical instruments of thattype having note playing mechanisms employing a tracker bar withopenings therein and. over which a perforated music sheet passes forcontrolling the playing mechanisms by predetermined registration of theopenings and perforations, and has to do more particularly with theconstruction, mounting and automatic adjustment of the tracker bar.

An object of the present invention is to improve all prior constructionsof adjustable tracker bars and their mountings wherein the tracker barscomprise a plurality of relatively movable sections, such as is shown inmy prior United States Patents Nos. 1,099,907 granted June 16th, 1914and 1,602,369 granted October 5th, 1926.

It is well known that, with the use of music sheets having thereinperforations and openings for controlling the playing mechamsm, thesesheets are subject to changes in width under different climaticconditions, and that the perforations and openings in the sheet,particularly toward the opposite longitudinal edges thereof, vary as todistances between them so that it is difficult to maintain the properregistration of the perforations and openings in the music sheet withthe tracker bar openings.

The invention more specifically, therefore, relates to certainimprovements in means for automatically adapting the tracker bar tovariations in the width of the music sheet.

In prior constructions of this general type, it has been customary toslidably support the sections of the tracker bar upon suitable guiderails, rods or the like, an arrangement which is open to manyobjections. In the first place, such a structure is a relatively eX-pensive one because of the accuracy and precision necessary in the partsin order toy prevent binding and maintain the sections in properrelation. Also, although the greatest care is taken in the manufactureand assembly of such a tracker bar, the same, after it has been in usefor some time, does not operate as smoothly and freely as it shouldbecause of excessive friction, wear between the parts, and theaccumulation of dirt on 1932. 'serial No. 612,500.

of sectional tracker bars is that there is a looseness in the pivotjoints and connections between the rods, levers and tracker bar sectionsof the adjusting mechanism, and this looseness naturally increases withwear and use and cannot be readily adjusted or taken taken up, andparticularly without throwing the mechanism out of proper balance orregistration with the music sheet.

It is, therefore, the purpose of the present invention to provide asectional tracker bar wherein there are no relatively sliding parts andconsequently wherein friction is eliminated, wherein the construction isan open one so that no diiiiculty may be encountered by Atheaccumulation of dirt in corners, grooves or crevices, and the like;wherein the trackerbar is at all times maintained practically level andcannot fall or move out of alignment; wherein there is no play or lostmotion in the operating mechanism; ywherein the tracker sections aresupported by rods, or the like, which are always under tension so as tomaintain the sections under tension at all times and preventinaccuracies in the relative positions and alignment of the sections;wherein less power is required for operating the tracker bar sections;and wherein a construction is provided which is considerably cheaper ascompared with prior constructions of this general character.

Other objects will be in part obvious and in part pointed out more indetail hereinafter.

The invention accordingly consists in the features of construction.combination of elestrips or ribbons.

ments and arrangement of parts which vill be exemplified in theconstruction hereinafter set forth and the scope of the application ofwhich will be indicated in the appended claims.

In the accompanying drawing:

Figure 1 is a fragmentary front elevation ot a tracker bar with itsoperating mechanisms constructed according to the present invention andshown in relation to a music sheet;l

Fig. 2 is a bottom plan view of the tracker bar: and

Fig. 3 is a transverse section taken through the central portion of thetracker bar.

Referring now to the drawing, designatos, generally, a tracker barformed in sections and which, in the present instance, has a middlesection 10a which is a fixed section, and tlie remaining sections aremounted for adjustment toward and away from the middle section. Thesections of the tracker bar 10 are supported upon a base board or strip11 which is mounted in the playing mechanism in suitable manner and maybe fixed against movement or may he connected for adjustment inaccordance with various devices used in connection with the playingmechanisms, and which have no relation to the present invention. Thisbar 11 is piovided with pairs ot rods 12, two pairs for cach section ofthe tracker bar 10. These rods are shown as being in the form of roundwires, but. obviously, they may compose flat The rods or arms of eachpair may be disposed in transverse alignment with respect to thesupporting bar 11 and the outer ends of the rods 12 are secured to theadjacent corner portions ot the respective tracker bar section, whilethe inner ends ot the rods 12 are fixed to the supporting bar 11. Therods 12 may be sprung outwardly toward the opposite ends of the trackerbar so that the sections of the tracker bar are urged into spaced apartor extended relation.

As shown particularly in Fig. 3, the supporting bar 11 may be providedat suitable spaced points along its opposite edge portions with socketopenin adapted to receive the inner ends of the rods 12, and may also beprovided with set screws 13, or the like, for fixing the rods 12 in thesocket openings.

The tracker bar 10 is adapted for use in the usual manner and receivesthereover a music sheet 14- supported in the usual manner by the playingmechanism and which has the usual note playing perforations, such asdesignated at 15, for registration with the openings 16 in the trackerbar to control the operation ot the playing mechanism.

The middle section 10a of the tracker bar, being a fixed section, hasits rods 12 anchored or socketed at their inner ends to the supportingbar 11, and their outer ends connected to the middle section in suchmanner as to place the rods 12 under desired tension to hold the middlesection rigidly in parallel relation with the supporting bar 11. Themounting of the end sections of the tracker bar 10 is such that they aresupported on substantially rectangular frames having a parallelogrammovement wherein the tracker bar sections are maintained in parallelrelation With the supporting bar or strip 11, and the movement is suchthat the displacement of the sections out ot the frontl plane of thetracker bar is negligible and is readily taken up by the tension underwhich the flexible music sheet is operated. Usually, the tracker barsare disposed with their outer ends or music sheet engaging faces insubstantially vertical position, and the supporting bar 11 is thusspaced inwardly or rearwardly in a horizontal direction from the trackerbar, and it will be noted that, as the rods 12 are placed under tensionand are rigidly connected at opposite ends to the tracker bar sectionsand to the supporting bar 11, there can be no sagging or dropping of thesections of the tracker bar out ot' alignment. The sections ot thetracker bar are thus yieldingly urged into separated relation, and theyare adapted to be moved together when required by the flexing orspringing of the rods 12. The rods 12 are of sufficient length, and areso proportioned, as to their inherent strength and resiliency, as toadmit of the proper support of the sections and so as not to offer toogreat resistance to flexing. The tracker bar sections are, therefore,rigidly mounted upon the supporting bar 11 and all sliding, pivoting andother frictioiial contact parts or surfaces are completely eliminated inthis construction.

In accordance with the present invention, the middle section 10a of thetracker bar, so far as variations in the length of the bar areconcerned, is fixed against movement, and the sections on opposite sidesof this fixed middle section are moved simultaneously but differentiallytoward the fixed section in the event that the music sheet shouldcontract in width, and are moved simultaneously away from the middlesection in the event th atV the sheet should expand crosswise. To thisend, there is provided a lever 17 pivoted, as at 19,A to a suitablesupport beneath or adjacent to the middle Section 10a, and which, in thepresent instance, is disclosed in the 'torni of a plate 19 which may besecured across the lower rods 12 ot' the middle section. The plate 19 isprovided with a central opening 20 of any suitable configuration whichregisters with the intermediate portion ot the lever 17, and the treeend of the lever may be offset inwardly to provide a lip 21 adapted forfrictional contact against the inner side of the plate 19 to steady thelever 17 in its movement. The pivot 18 of the lever is disposed at theouter end of the plate 19 and is spaced inwardly from the adjacent endof the lever 17 so as to provide a short arm of the lever outwardly ofor beyond the pivot 18. The sections of the tracker bar, to one side ofthe middle section a, are connected by links 22 to the lever 17 at oneside of its pivotal point 18, and the sections to the other side of theymiddle section 10a are connected by links 23 to the lever 17 at theopposite side of its pivotal point 18. Thus, when the lever 17 isturned, the sections of the tracker bar 10 to the left hand side of thefixed middle'section 10a will move in one directiom'and the sections onthe right hand side will move in the opposite direction. It will benoted that the links for the two sections of the tracker bar areconnected to the lever 17 at points further removed from the pivot 18 ofthe lever than kare the links connected to the intermediate sections,the object of thisr arrangement being to cause the outer sections tomove greater distances than the intermediate movable sections and thustake care of the accumulated expansion and contraction of the musicsheet from the center to the edges thereof. In actual practice, thetracker bar may be made of more than five sections, as shown.

As the rods 12 of the outer sections of the tracker bar 10 normally urgethe tracker bar sections to separate or expand, there is a normaltendency exerted upon the lever 17 through the links 22 and 23 to turnthe lever 17 in one direction. To counterbalance or neutralize thismovement of the lever 17, the lever is provided with a counterbalancingspring 24which, at one end, is connected to the lever 17 and, at itsother end, is anchored to the supporting bar or strip 11 towards one endthereof, as shown in Fig. 2, and the adjacent set screw 13 may beutilized for this purpose.

The spring 24 may be connected to the lever 17 in any suitable manner.In the present instance, one end thereof is connected to the flattenedend or lug 25 of an operating rod 26 which is pivotallyT connected, asat 27 to the freeend portion of the lever 17 This spring is soproportioned and is yplaced un der such tension as to substantiallycounter-balance the spring action of the arms and lthus maintain thetracker sections in any position of adjustment until that position ofadjustment is disturbed by suitable operating means controlled by themusic sheet. This operating means or mechanism may take any suitableform but, by way of illustration only. I have shown, in the accompanyingdrawing, a mechanism somewhat similar to that illustrated'in my PatentNo. 1,602,369 dated Octo- 'U3 say that the operating means includes apair of oppositely acting pneumatics 28 and 29 connected to the rod 26as through a bar 31, and these pneumatics are associated by suitabletubes 32 and 33 with ports 34 and 35 in one of the end sections of vthetracker bar. These tubes 32 and 33 communicate by means of small bleedopenings 36 and 37 with an exhaust chamber 39. The note sheet may beprovided with a continuous line of spaced perforations or holes 38which, when the note sheet is properly tracking, will pass over thetracker bar between the ports 34 and 35. It is understood, of course,that, in the event the music sheet should increase in width, the portwill be uncovered with the result that the tracker bar sections will bemoved farther apart. In the event that the note sheet i should becomenarrower, the line of holes 38 will uncover the port 34, whereupon thepneumatic 29 will turn the lever 17 counterclock- Wise and, thereby,move the tracker sections towards each other.

It will be observed that, with my improved construction, the tracker barsections are so supported that friction is entirely eliminated and anydanger of dust or foreign matter interfering with the sensitive actionof these sections is entirely avoided. Since wear is entirelyeliminated, there is no possibility of the introduction of loose playbetween the sections and, therefore, the accuracy and sensitiveness ofthe tracker bar are retained throughout the life of the musicalinstrument in which it is embodied. The arrangement provides a verysimple one which can be cheaply manufactured and which requires but verylittle power or energy in its operation. The sections have a somewhatswinging movement, and this movement is so small as to be simultaneouslynegligible insofar as the disturbance of the alignment of the perforatedsurfaces of the sections is concerned, these surfaces being maintainedsubstantially in the same plane at all times so that there is always aneffective seal between each of the sections and the note sheet passingthereover. The inherent resiliency of the supportingr rods 12 tends todraw the sections apart, and this action is substantiallycounterbalanoed at all times by the spring 24 so that everything` isunder tension, so to speak, and there is no lost motion between theoperating means and the sections. Any wear which may take place in theconnections between the operating means and the sections isautomatically taken up. More particularly, it will be noted that theinherent resiliency of the rods always exerts a pulling force on theconnecting links 22 and 23.

As many changes could be made in the above construction and manyapparently widely different embodiments of this invention could be madewithout departing from the scope thereof, it is intended that all mattercontained in the above description or i might be said shown in theaccompanying drawing shall be interpreted as illustrative and not in alimiting sense.

It is also to be understood that the lanf guage used in the followingclaims is intended to cov r all of the generic and specific 'features otthe invention herein described and all statements of the scope of theinvention wh= li, as a. matter orn language, to tall therebetween; forexample, the word rodsf7 as employed in the claims, is intended toinclude resilient supporting members of various kinds incluuing flatr'bbons or strips.

I claim as my invention:

l. in e tra'l I.. bar mechanism for musical instruments, trackercomprisinga pluraliti7 of sections movable lengthwise `towards and e "iyfrom cach other, tension means norm y urging said sections away fromeach other, and operaingmeans adapted to controlled by the music sheepassing over the trackerbar sections tor changing the length ot saidbar.n

In a tracker bar Aechanism ror musical instruments. a tracker arcomprising a pluof sections movable lengthwise toand away from eachother, tension means normally said sections away from each othe, addional tension means substantially couuterbalancing said first tenq1- mi.

wards sion means. and operating' means adapted to be controlled by themusic sheet passing over the tracker bar sections for changing thelength of said bar. s

3. in a tracker our mechanism loi nuisical instruments, tracker bai'compnsing a plurality7 of sections movable lengthwiseL towards and awayfrom eacn other, and iension means tor supporting said sections inlengtl'iwise alignment.

Il. In a tracker bar mechanism for musical instruments, a tracker barcomprising a plurality ol' sections movable lengthwise towards and awaytroni each other, tension means for supporting said sections. inlengthwise alionnien, a ing substfrintially counerbalancing the ensionot said supporting means, and ope ating means for changing the lenfi'thoi said bar.

5. Ina tr cker bar mechanism for musical instrumentsr` a tracker barcomprising a pluof sections movable lengthwise torom each other, andsupirtino; iii-cans 'oi said sections comprising lent rods.

In a tracker bar inechsnisn'i for musical ins"ruin-cnts, a tracker barcompiisigna plurality of section ovable lengthwise towards and away fromeach other, and supporting' means i'or said sections comprisingresilient rods, said rods being anchored at one end and being connectedat their other ends to the respective sections.

7. In a tracker bar mechanism for musical instruments, a' tracker barcom rising a plurality of sections movable lengt wise to# wards and awayfrom each other, a fixed support, resilient supporting rods anchored atone end to said support and fixedly connected at their other ends to therespective sections of the bar, and means connected to said rods forchanging the length of the bar.

8. In a tracker bar mechanism for musical instruments, a tracker barcomprising a plurality of sections movable lengthwise towards and awayfrom each other, and a pluralit of resilient supporting rods eachanchore at one end and arranged to support said tracker sections inlongitudinal alignment, each of said sections being supported by atleast two rods connected to the opposite ends thereof.

9. In a tracker bar mechanism for musical instruments, a tracker barhaving a plurality of sections movable lengthwise towards and away froma central fixed section, tension means for supporting said movablesections in substantial alignment and in spaced rela,- tion, and meansfor moving said movable sections towards said central section.

lO. In a tracker bar mechanism for musical instruments, a tracker barhaving a plurality ot sections movable lengthwise towards and away froma central fixed section, resilient supporting rods for said movablesectlons, and means for flexing said rods to move said sections towardsthe fixed one.

11. In a tracker bar mechanism for musical instruments, a plurality oflengthwise separable tracker bar sections biased towards relative spreadpositions, tension means operable on said sections counter to the biasfor maintaining the sections under tension in counterbalanced normalrelative positions highly sensitive to movement in opposite directionsout of their normal positions, and tracker bar lengthening andcontracting means controllable by the music sheet to move said sectionsof the tracker bar towards and away from each other.

l2. In a tracker bar mechanism for musical instruments, a supportingstrip, a plurality of tracker bar sections spaced from said strip and insubstantial alignment with each other, spring arms fixed at oppositeends to the supporting strip and to said sections and arranged tosupport the sections in longitudinal alignment and in spaced apartrelation, a pivoted lever, corrections between said sections and thelever and disposed to draw said sections together upon the turning ofthe lever in one direction and to permit said sections to spread apartunder the influence or said arms when the lever is turned in theopposite direction, and tension means connected to said lever andcounter-balancing the inherent resiliency of said arms.

